Earth's life from its inception to the present day
Earth is the third planet in the solar system, away from the Sun after Mercury and Venus.It is the largest terrestrial planet in the solar system, in terms of its diameter, mass and density.This planet is also called the world.
The land is home to millions of species
Of living beings, including man; it is the only known place of life in the universe. Earth was formed about 4.54 billion years ago, and life appeared on its surface in the last billion years. The Earth's biosphere has since changed the atmosphere and abnormal conditions on the planet, allowing the reproduction of organisms living only in the presence of oxygen and the formation of the ozone layer, which works with the Earth's magnetic field to block harmful radiation, allowing life to exist on the surface. Earth. The ozone layer obscures ultraviolet rays, and the Earth's magnetic field displaces and removes charged primary particles from the sun at great speeds and keeps them in outer space away from Earth, causing no harm to living organisms. Life is expected to last for another 1.2 billion years, after which increased sunlight will spend on the Earth's biosphere, where scientists believe that the sun will P temperature in the future and expand and grow up to become a giant red and up diameter of Venus or even to the Earth's orbit, as they see the development of similar to the sun in the universe of stars when near the end of the age of the star and the entry into force of its fuel from hydrogen.
The sun's high temperatures end life on Earth. This is if no other cosmic event has ever happened before - like the explosion of a nearby star in the form of a supernova - that ends life on it.
More than 7.7 billion people live on Earth,
The Earth's various resources keep a huge global population of people, who share the world among themselves and are divided into about 200 independent countries, and have developed diverse societies, civilizations and cultures, and interact with each other in a variety of ways, including diplomatic communication, tourism, trade and military combat as well. Human culture has different looks and representations of the earth. Some ancient civilizations have represented their goddess, some thought it flat. That will ultimately threaten man himself.
Earth
The Earth is in the Solar System's planets group, and the Solar System itself is one of the hundreds of billions of stars that make up the Milky Way or the Milky Way. The region that distinguishes the planet around the sun from the other is an area known to be habitable, meaning that the Earth's distance from the sun, which is about 150 million kilometers and the Earth's orbit around the sun in a circular orbit makes it suitable temperatures not too high and not too cold to suit the emergence Lives and continuing them. In addition, the Earth has an adequate size to retain its atmosphere, the presence of water on it, the presence of ozone gas in the Earth's atmosphere, which protects it from harmful ultraviolet rays, as well as its magnetic field, which protects it from the rapid elementary particles that come with the solar wind, threatening the integrity of the Earth's biology .
The outer surface of the earth is divided into several parts:
The solid earth crust, which reaches a depth of about fifty kilometers, the earth's atmosphere, which reaches a thickness of 4000 kilometers, and the core of the central solid ground consisting of iron and nickel. The Earth's envelope is in a liquid electrically conductive state where its motion creates the Earth's magnetic field. The crust is floating above the molten Earth's atmosphere. The Earth's crust is divided into a number of great tectonic plates, which gradually emerged on the surface of the Earth because of its coolness gradually over millions of years. The relatively thin crust floats above the so-called geosphere, a large part of the Earth's mass, and consists of a very hot magma beneath the crust at a temperature of about 1,700 degrees Celsius and increases in rate as it approaches the Earth's iron center. This magma is carried out in different directions on the ground of the crust forming what we know of volcanoes. Water covers about 71% of the Earth's surface in the oceans and is a salty water that is full of aquatic life, while the rest consists of continents, islands, and rivers, freshwater necessary for life on land in all forms of plants and animals.
So far no life has been found on any of the other planets, but the probe that landed on Mars may suggest life in the form of primitive organisms that did not evolve much before the alleged life on Mars ended after the weather deteriorated. Some scientists explain the images of the probe by saying that there is a possibility of life on Mars in the past, but the chapter in this regard requires huge efforts, and send devices and equipment that can do the analysis of samples or return them to Earth for study and analysis.
The Earth's active subsoil has a thick middle layer, about 4,000 kilometers thick.It forms the Earth's atmosphere, a relatively solid liquid, and scientists divide it into a highly viscous liquid outer core, sometimes emerging as magma to the surface when volcanoes are active. The outer core is in a constant motion that generates the Earth's magnetic field. The inner core is very dense, and its density increases with increasing proximity to the central core of the Earth, which is about 7 grams / cubic centimeter.The inner core is mainly iron and nickel, and the nucleus of the earth takes a spherical shape with a radius of about 2000 km In addition, the planet is affected by the planets in outer space, especially the sun where it orbits and the moon, which orbits around the Earth. At present, the Earth revolves around the Sun once every 366.26 days, in addition to its orbit. This period of time for its orbit around the sun is called an "astronomical year" equivalent to 365.26 solar days. The Earth's axis of rotation tilts itself 23.4 degrees from its vertical orbit around the Sun, resulting in the diversity of seasons on the planet.
The Earth has a single natural satellite, the Moon, which orbited it 4.53 billion years ago. The moon's rotation around the Earth results in the emergence of the tidal phenomenon, which occurs in water bodies, maintaining the stability of the Earth's axis of inclination and the gradual slowing of its rotation. The Earth's surface was influenced by asteroids that fell about 4.1 to 3.8 billion years ago, leading to changes in the surface environment.
Mineral resources of the planet and resources in the biosphere are sources of population distribution on Earth. The population of the Earth is concentrated in about 200 countries, each of which has independent sovereignty over its territory, and deals with each other through diplomatic, tourism, trade, and military relations. There are many perspectives adopted by different human cultures about the planet, including the sanctification of the earth to the point of slavery. It was believed in the past that the earth is flat, and did not discover the spherical rights of the earth only in the Middle Ages after the improvement of scientific methods, although all Muslim scholars unanimously agreed that the earth is spherical, where Ibn Hazm (d. 456 AH):
«And our answer and God Almighty to reconcile that one of the imams of Muslims worthy of the name of the Imamate science did not deny the pelleting of the earth and does not preserve one of them in the payment of the word, but the proofs of the Koran and the Sunnah has come pelletizing» - chapter in boredom and whims and bees (2/78)
The environment on Earth allows life because of its proper distance from the sun, and the presence of water, oxygen, carbon and nitrogen, which is the living substance, an integrated environment that needs to be preserved, and not to damage the human life lose its presence and its ability to survive, and some other neighborhoods may also disappear because of the exploitation of human resources of the earth No account.
Chronology of events on the planet
Scientists have been able to gather detailed information about the past epochs of the planet. It is a disc-shaped mass of dust and gas left from the formation of the sun. The formation of the earth by these outer parts was completed within 10 to 20 million years. At first, the earth was melted, and its outer layer cooled to form a hard shell when water began to accumulate in the Earth's atmosphere. The moon was formed shortly thereafter, when a celestial body - the size of Mars (sometimes called the Impact Impact Impact Hypothesis), which accounts for 10% of the Earth's mass - collided with the Earth in an accidental shock. Parts of this orb merged with the planet, and parts of it were scattered in space, but parts of that orbiter settled in orbit and formed the moon. Volcanic activity and the emission of gases from the planet have created the planet's core atmosphere. The oceans consisted of condensation of water vapor, which was augmented by snow and liquid water carried by asteroids, larger native planets, comets and any planet in the Sun's system orbiting the Sun further away from Neptune. Two main possibilities have been proposed for the form of continental development: the first is the constant evolution that continues to the present era, and the second is an initial rapid development that occurred early in the history of the Earth. Research has shown that the second theory is the closest to the truth. There has been a rapid and initial evolution of the continental crust, followed by a long-term steady development of the continental region. Measured by time scale, it has persisted for hundreds of millions of years as the surface of the planet continually reshaped itself as the continents formed, and subsequently split. The estates diverged and moved on the surface of the earth, but sometimes they gathered again to form a large continent. The continent, "Rodinia" one of the oldest large continents that appeared about 750 million years ago, and then began to separate. Then, the continents reunited to become the great continent, Panotia, between 600 and 540 million years, and eventually formed the continent of Pangea, which separated parts 180 million years ago.
The Origin of Life on Planet Earth
Until now, the planet is the only planet on which there is a life-sustaining environment. About 4 billion years ago, the energy-filled chemical reactions that occurred on the planet resulted in molecules with the potential to multiply themselves.After nearly half a billion years later, the organism or strain from which later species evolved on Earth emerged. Photosynthesis (the synthesis of chemical compounds in light) allows the energy from the sun to be directly exploited in life in all its forms; oxygen from this process accumulates in the atmosphere forming the ozone layer (O3) in the upper part of the atmosphere. This theory explains the origin of mitochondria and chloroplasts (parts of plant cells containing chlorophyll) that are subunits of eukaryot cells (lacking the nucleus and nuclear membrane). The fusion of small cells within large cells results in the formation of complex cells called eukaryotic cells (that is, they are characterized by a single nucleus). Real multicellular organisms formed in the form of cells within colonies take on more specific traits. Thanks to the absorption of the ozone layer of harmful ultraviolet rays, life has settled on the surface of the planet.
During the 1960s, some scientists hypothesized that a severe snowstorm blew on Earth between 750 and 580 million years during the Neolithic period, covering most parts of the planet with sheets or ice sheets. The term "Earth is a snowball" on this assumption, and this event is of great interest because it precedes the Cambrian explosion, when multicellular organisms began to appear on the surface of the planet. After the Cambrian explosion, about 535 million years ago, five major extinctions occurred. The last extinction occurred 65 million years ago, when a meteorite collided with the Earth extinction of dinosaurs and other large reptiles, but small animals such as mammals, which at the time resembled the shrew (mouse-eating insects), remained different. For 65 million years, a monkey-like ancestor was able to stand on her legs upright for millions of years, according to Darwin's theory.This led to the development of her ability to use tools and encourage interpersonal communication - which in turn contributed to a more efficient supply of food. And created antiques G appropriate, which helped eventually to increase the size of the brain, and the arrival of human to what it is today according to this theory. At the same time, the emergence of agricultural activity and civilizations led to a significant impact on the Earth in a short period of time, which never happened before - which in turn affected other forms of life in nature and quantity. The current pattern of ice ages began about 40 million years ago, and intensified during the earliest modern era about 3 million years ago. The polar regions have since undergone repeated cycles of precipitation and melting of ice, repeated every 40 to 100,000 years, and the last ice age ended 10,000 years ago.
Learn about the future of the Earth in the next article by clicking on the following link
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